Here are some sharp, strange, and true FactSlaps about Friday the 13th—the day, the fear, and the franchise:

• Triskaidekaphobia is the fear of the number 13. The more specific fear of Friday the 13th is called paraskevidekatriaphobia—a word that sounds cursed just trying to pronounce it.

• The origins of Friday the 13th fear are murky, but one theory traces it to October 13, 1307, when hundreds of Knights Templar were arrested and tortured by order of France’s King Philip IV. It was a Friday.

• Statistically, Friday the 13th is no more dangerous than any other day—yet American businesses lose $700 million to $900 million in productivity every time it rolls around, due to canceled meetings, flights, and general avoidance.

• Many buildings skip the 13th floor, airports skip Gate 13, and some cities skip 13th Street altogether. Superstition still builds modern architecture.

• The Friday the 13th film franchise—starting with the 1980 slasher—has grossed over $1.1 billion (adjusted for inflation), making it one of the most profitable horror franchises ever. Jason Voorhees may wear a mask, but he’s laughing all the way to the bank.

• In Finland, they mark every Friday the 13th with a National Accident Day, promoting awareness for workplace and traffic safety. Only the Finns could make a horror day more boring than terrifying.

• There can be up to three Friday the 13ths in a year, but there is at least one every year—thanks to the Gregorian calendar’s quirks.

• The 13th of a month is more likely to fall on a Friday than any other day of the week. It’s not unlucky—it’s just math.

• The Apollo 13 mission launched at 13:13 Central Time on April 11, 1970. Though not on a Friday, it famously failed after an oxygen tank exploded—cementing 13’s cosmic rep as a number to watch.

• Despite the fear, more people are born on the 13th than any other date of the month. So if you’re superstitious, just remember: the world is full of lucky 13s walking around.